A fresh system is tipped to make the next few days rainier in Calcutta, the Met office has said.

Some districts are likely to get heavy rain.

“An upper air cyclonic circulation lies over the northwest Bay of Bengal and adjoining north Odisha-Bengal coasts extending up to 7.6km above mean sea level. Under its influence, a low-pressure area is likely to form over the same region during the next 24 hours,” said a Met bulletin issued on Wednesday.

“Under its influence, light to moderate rainfall at most places with isolated heavy rainfall is very likely in some districts of south Bengal during next three days and thereafter, due to favourable wind pattern and strong moisture incursion from the Bay of Bengal, isolated heavy to very-heavy rainfall is very likely in some districts of north Bengal from June 27 to 30,” it said.

On Wednesday, Calcutta woke up to a hot and sunny morning, but the sky turned cloudy in the afternoon, and a spell of rain followed. The Met office recorded just above 5mm of rain in Alipore between Wednesday morning and night.

“Calcutta is expected to get more than one spell of rain on Thursday. Friday is also expected to be wet. The rain will be light to moderate in Calcutta,” said H.R. Biswas, head of the weather section at the Regional Meteorological Centre in Alipore.

The temperature is unlikely to shoot up anytime soon, he said.

The northern parts of Odisha are expected to be more affected by the system, according to Met officials. It is likely to rise from its current position, they said.

On Thursday, heavy rain (7-11cm) is expected in West Burdwan, West Midnapore, East Midnapore and Jhargram, according to the forecast. On Friday, heavy rain is expected in East Burdwan, West Burdwan, Birbhum, Jhargram, West Midnapore, Purulia and Bankura.